#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
int main()
{
	int a = 0;
	int n;
	int i;
	int arr1[9] = { 1,2,3,4,5,1,2,3,4 };
	for (n = 0; n < sizeof(arr1)/sizeof(arr1[0]); n++)
	{
		for (i = n+1; i < sizeof(arr1) / sizeof(arr1[0]); i++)
		{
			a = 0;
			if (arr1[n] == arr1[i])
			{
				a++;
				break;
				
			}
			
		}
		if (a == 0)

		{
			printf("%d", arr1[n]);
			break;
		}
		
	}
	return 0;
}